from Scientific American
Dmitri K. Belyaev, a Russian scientist, may be the man most responsible for our understanding of the process by which wolves were domesticated into our canine companions. Dogs began making for themselves a social niche within human culture as early as 12,000 years ago in the Middle East. But Belyaev didn't study dogs or wolves; his research focused instead on foxes. What might foxes be able to tell us about the domestication of dogs?
Domesticated animals of widely different species seem to share some common traits: changes in body size, in fur coloration, in the timing of the reproductive cycle. Their hair or fur becomes wavy or curly; they have floppy ears and shortened or curly tails. ... And domesticated animals possess characteristic changes in behavior compared with their wild brethren, such as a willingness or even an eagerness to hang out with humans.
Belyaev and other Soviet-era biologists looked around at domesticated dogs, a species they knew had descended from wolves, and were puzzled. They could not figure out what mechanism could account for the differences in anatomy, physiology, and behavior that they saw in dogs, but they knew that they could find the answers in the principles of Mendelian inheritance. ...
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from BBC News Online
Climate change is not responsible for civil wars in Africa, a study suggests. It challenges previous assumptions that environmental disasters, such as drought and prolonged heat waves, had played a part in triggering unrest.
Instead, it says, traditional factors--such as poverty and social tensions--were often the main factors behind the outbreak of conflicts. The findings have been published in the Proceedings of the National Academy of Sciences (PNAS) in the United States.
"Climate variability in Africa does not seem to have a significant impact on the risk of civil war," said author Halvard Buhaug, senior researcher at the Peace Research Institute Oslo's (Prio) Centre for the Study of Civil War.
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from the Economist
Once, they were grim places of bars and concrete. But zoos today are, more often than not, places where endangered species are bred in verdant and naturalistic enclosures. At least, that is what the public sees.
As night falls and the facilities need to be cleaned, the animals are commonly led into small concrete holding areas. For decades zoos around the world have used such areas without question and assumed that their effects on the animals' behaviour were negligible so long as high-quality enclosures were available during the day. This notion may, however, be wrong, for a new study shows that, at least among the great apes, holding areas have a dramatic effect on behaviour.
While working with chimpanzees and gorillas, Stephen Ross, a primatologist at Lincoln Park Zoo in Chicago, noticed that the animals changed their behaviour when they were moved in and out of the holding areas. Curious as to whether these changes were happening regularly, and keen to identify specifically how behaviour was changing, Mr. Ross and a team of his colleagues decided to carry out an experiment.
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from the San Diego Union-Tribune (Registration Required)
WASHINGTON (Associated Press) -- Sophisticated computer models that replaced instinct with cold, hard math have helped forecasters predict where a storm like Hurricane Earl is going about twice as accurately as 20 years ago.
And last year, they proved it: The three-day forecast was as accurate as the here-it-comes, one-day warning used to be in the 1980s. In the 2009 hurricane season, the one-day forecast predicting where a storm would hit was off by only 53 miles on average.
But Earl is the type of storm--big and in a tricky location--that can defy expectations. Its predicted track shows the eye passing just off the East Coast, dancing so close to shore that a slight wobble could turn that miss into a mess. Even if the eye remains offshore, high winds that extend 200 miles from the center could reach inland.
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from Nature News
A new test can accurately diagnose tuberculosis (TB) in people in 90 minutes, compared with the six weeks needed for the current standard test.
The Xpert MTB/RIF test, described Wednesday in the New England Journal of Medicine, identifies TB in 98% of active cases--an improvement of more than 45% on one of the most commonly used current techniques. It also detects whether the TB-causing bacteria are resistant to rifampicin, a first-line drug for TB, in nearly 98% of cases.
"It has the potential to be revolutionary," says Richard Chaisson, director of the Johns Hopkins Center for Tuberculosis Research in Baltimore, Maryland, who was not involved with the work. A single test can also diagnose TB in 72% of those infected with both HIV and TB, which the current standard smear cannot do at all.
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from the New York Times (Registration Required)
OPELOUSAS, La. -- At 18 months, Kyle Warren started taking a daily antipsychotic drug on the orders of a pediatrician trying to quell the boy's severe temper tantrums.
Thus began a troubled toddler's journey from one doctor to another, from one diagnosis to another, involving even more drugs. Autism, bipolar disorder, hyperactivity, insomnia, oppositional defiant disorder. The boy's daily pill regimen multiplied: the antipsychotic Risperdal, the antidepressant Prozac, two sleeping medicines and one for attention-deficit disorder. All by the time he was 3.
He was sedated, drooling and overweight from the side effects of the antipsychotic medicine. Although his mother, Brandy Warren, had been at her "wit's end" when she resorted to the drug treatment, she began to worry about Kyle's altered personality. "All I had was a medicated little boy," Ms. Warren said. "I didn't have my son. It's like, you'd look into his eyes and you would just see just blankness."
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from National Geographic News
Evolution has been caught in the act, according to scientists who are decoding how a species of Australian lizard is abandoning egg-laying in favor of live birth.
Along the warm coastal lowlands of New South Wales, the yellow-bellied three-toed skink lays eggs to reproduce. But individuals of the same species living in the state's higher, colder mountains are almost all giving birth to live young.
Only two other modern reptiles--another skink species and a European lizard--use both types of reproduction. Evolutionary records shows that nearly a hundred reptile lineages have independently made the transition from egg-laying to live birth in the past, and today about 20 percent of all living snakes and lizards give birth to live young only.
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from the Telegraph (UK)
God did not create the universe, Stephen Hawking revealed yesterday. In the flurry of publicity preceding his new book, The Grand Design, to be published next week, he does some serious dissing of the Almighty, declaring him/her/it irrelevant. The point is, he says, that our universe followed inevitably from the laws of nature. But, we might ask, where did they come from?
It is perhaps a bit rich for Hawking to make God redundant after granting him/her/it a celebrity cameo at the end of his multi-million selling A Brief History of Time. In his famous conclusion to the book, Hawking wrote that if scientists could find the most fundamental laws of nature "then we should know the mind of God." To be fair, he was writing metaphorically--we all know what he meant.
He now suggests that the search for this particular Holy Grail is over, now that scientists have come up with a type of theory, known as M-theory, that may describe the behaviour of all the fundamental particles and force, and even account for the very birth of the universe.
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from Science News
Mental exercise lets seniors outrun Alzheimer's disease--for a while. Then the race takes a tragic turn for the sharp-minded, a new study finds, as declines in memory and other thinking skills kick into high gear.
After age 65, regular participation in mentally stimulating activities, including doing crossword puzzles and reading, delays intellectual decay caused by Alzheimer's disease, say neuropsychologist Robert Wilson of Rush University Medical Center in Chicago and his colleagues. But when this debilitating condition finally breaks through the defenses of a mentally fortified brain, it rapidly makes up for lost time, the scientists report in a paper published online September 1 in Neurology.
"The benefit of delaying initial signs of cognitive decline by keeping mentally active may come at the cost of more rapid dementia progression later on," Wilson says.
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from BBC News Online
Orcas, commonly known as killer whales, are still evolving, and quickly. Researchers have discovered that two distinct types of orca, a large and a pygmy form, are rapidly diverging, evolving away from each other.
The scientists' study reveals each type of orca carries a unique gene mutation that benefits its particular lifestyle. The genetic change has occurred in the past 150,000 years, adding to evidence that the orcas are quickly evolving into two distinct species.
Details of the research are published in the journal Biology Letters by an international team of scientists led by orca expert Dr. Andrew Foote of the Natural History Museum of Denmark based at the University of Copenhagen.
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from ScienceNOW Daily News
A nose full of biting ants can really spoil your appetite. Especially if your nose is 3 meters long. African bush elephants (Loxodonta africana) avoid this discomfort by refusing to munch on acacia trees that house swarming ant colonies. Their aversion, a new study suggests, helps maintain the savanna's delicate balance between forest and prairie.
Trees and grasses constantly vie for control of the savanna, but wildfires, drought, variable soil chemistry, and giant herbivores prevent either plant from taking over. Not enough fire to keep the trees in check, and the canopy will close in; too many elephants eating the trees, and the savanna would become grassland. Or so scientists thought. They seem to have underestimated the acacia's ability to defend itself.
Unlike many acacia trees that are stripped bare by elephants, whistling thorn trees (Acacia drepanolobium) seemed immune. The trees bristle with the 5-centimeter-long thorns typical of many acacias, but some of the spikes also swell into hollow bulbs the size of ping pong balls. Crematogaster ants colonize the empty thorns and feed on nectar secreted from the plant's leaves.
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from the Christian Science Monitor
A striking galaxy buzzing with energetic star formation takes center stage in a new photograph that showcases an unusual "superwind" of out-flowing gas, researchers say.
The starburst galaxy NGC 4666, located about 80 million light-years away from Earth, is a hotbed of intense star formation, which is thought to be caused by gravitational interactions between NGC 4666 and its neighboring galaxies, one of which is visible in the lower left of the new photo.
Gravitational interactions between galaxies often trigger the type of rigorous star formation seen in NGC 4666. Strong winds from the massive stars inside NGC 4666, combined with supernova explosions, drive a robust flow of gas--a so-called "superwind"--from the galaxy into space, according to the European Southern Observatory where astronomers took the new photo.
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from the New York Times (Registration Required)
In a year when news about Alzheimer's disease seems to whipsaw between encouraging and disheartening, a new discovery by an 84-year-old scientist has illuminated a new direction.
The scientist, Paul Greengard, who was awarded a Nobel Prize in 2000 for his work on signaling in brain cells, still works in his Rockefeller University laboratory in New York City seven days a week, walking there from his apartment two blocks away, taking his aging Bernese mountain dog, Alpha.
He got interested in Alzheimer's about 25 years ago when his wife's father developed it, and his research is now supported by a philanthropic foundation that was started solely to allow him to study the disease. It was mostly these funds and federal government grants that allowed him to find a new protein that is needed to make beta amyloid, which makes up the telltale plaque that builds up in the brains of people with Alzheimer's.
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from National Geographic News
A new generation of nuclear power technology seeks to transform one of the industry's most enduring problems--its radioactive waste--into an energy solution.
The idea is to reprocess that spent fuel to generate more power. Proponents say the know-how is available now to address the nuclear proliferation concerns that have bedeviled previous recycling plans. And they say the advanced reactors that would run on that recycled fuel would mark a new level of progress on safety.
Nuclear critics remain skeptical, especially because the industry is calling on government to bear the large expense of building the first plants to demonstrate the technology. But given the urgency of climate change ... the industry and its supporters are saying that the Integral Fast Reactor (IFR), which has been studied for decades, is worth a new look.
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from the Los Angeles Times (Registration Required)
Preemptive removal of breasts or ovaries in women with two common breast cancer genes can sharply reduce the risk of contracting cancer and dying, even if a woman has already been diagnosed with breast cancer, a new study confirms.
Researchers were already confident that such prophylactic surgeries reduce the risk of cancer, but the new study, reported Tuesday in the Journal of the American Medical Assn., is the largest such investigation to date and the first to differentiate the benefits based on which gene a woman has and whether or not she has already had cancer. It is also the first to show a survival benefit.
Removal of the ovaries and ovarian tubes in women with either the BRCA1 or BRCA2 genes can almost completely eliminate the risk of ovarian cancer and reduce the risk of breast cancer by about two-thirds, the study found. Removal of breasts can reduce the risk of breast cancer by as much as 85%. Either procedure reduces the risk of dying by at least two-thirds.
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from Scientific American
Milk is well known as a great dietary source of protein and calcium, not to mention an indispensable companion to cookies. But "nature's perfect food," a label given to milk over time by a variety of boosters, including consumer activists, government nutritionists and the American Dairy Council, has become a great source of controversy, too.
The long-running dispute over whether milk, both from cows and goats, should be consumed in raw or pasteurized form--an argument more than a century old--has heated up in the last five years, according to Bill Marler, a Washington State lawyer who takes raw milk and other food poisoning cases.
A bumper crop of recent illness related to raw milk accentuates the problem. Last month, at least 30 people, including two children, tested positive for strains of Campylobacter and Escherichia coli bacteria traced to raw (nonpasteurized) goat milk.
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from the New York Times (Registration Required)
Why are worker ants sterile? Why do birds sometimes help their parents raise more chicks, instead of having chicks of their own? Why do bacteria explode with toxins to kill rival colonies? In 1964, the British biologist William Hamilton published a landmark paper to answer these kinds of questions. Sometimes, he argued, helping your relatives can spread your genes faster than having children of your own.
For the past 46 years, biologists have used Dr. Hamilton's theory to make sense of how animal societies evolve. They've even applied it to the evolution of our own species. But in the latest issue of the journal Nature, a team of prominent evolutionary biologists at Harvard try to demolish the theory.
The scientists argue that studies on animals since Dr. Hamilton's day have failed to support it. The scientists write that a close look at the underlying math reveals that Dr. Hamilton's theory is superfluous. "It's precisely like an ancient epicycle in the solar system," said Martin Nowak, a co-author of the paper with Edward O. Wilson and Corina Tarnita. "The world is much simpler without it."
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from Nature News
Quantum hackers have performed the first 'invisible' attack on two commercial quantum cryptographic systems. By using lasers on the systems--which use quantum states of light to encrypt information for transmission--they have fully cracked their encryption keys, yet left no trace of the hack.
Quantum cryptography is often touted as being perfectly secure. It is based on the principle that you cannot make measurements of a quantum system without disturbing it. So, in theory, it is impossible for an eavesdropper to intercept a quantum encryption key without disrupting it in a noticeable way, triggering alarm bells.
Vadim Makarov at the Norwegian University of Science and Technology in Trondheim and his colleagues have now cracked it. "Our hack gave 100% knowledge of the key, with zero disturbance to the system," he says.
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from BBC News Online
An ancient reef found in the Pacific may provide clues to what will happen to coral when sea temperatures rise. A team of researchers from Australia and New Zealand have discovered a huge 9,000-year-old reef surprisingly far south.
Lord Howe Island is 600km east of the Australian mainland and has a small modern coral reef--the furthest south in the world. The ancient reef however is nearly 30 times as large as the modern reef.
The scientists, headed by Colin Woodroffe from the University of Wollongong in Australia and researchers from Geoscience Australia, discovered a large ridge about 30m under water in the Tasman Sea. They have published their work in Geophysical Research Letters. The team suspected it might be an ancient reef. The size and shape of the ridge can be mapped using a type of sonar called multi-beam echo sounding. The researchers could not be sure it was coral until they had taken samples.
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from the Philadelphia Inquirer
Congratulations. You've blown some insulation into the attic, screwed in some compact fluorescent lightbulbs. Perhaps you replaced those old, drafty windows. Energy-saving moves, all of them. But that's nothing compared to what is coming at the Navy Yard.
Pennsylvania State University and a slew of partners plan to implement and develop the very latest in eco-friendly technologies at the South Philadelphia site, with the help of $159 million in federal and state grants announced last week.
"Dynamic" building facades that adjust in response to changes in outdoor temperature and sunlight. High-tech materials that remove humidity from the air without cooling it to the bone-chilling level of the typical air conditioner. Electronic sensors that perceive harmful particles in the air and activate filters when needed.
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from Nature News
The humble Antarctic krill (Euphausia superba) bears a heavy burden. It may be just a small, shrimp-like crustacean, but its sheer abundance makes it one of the largest protein sources on Earth, eagerly sought by fish, penguins, whales--and man.
Ecologists are now warning that the rapid growth in krill fishing is adding to the pressure of environmental changes threatening the creatures, and are calling for better monitoring and precautionary management of krill fisheries.
The global fish-farming industry is increasingly relying on krill-based fish feed, and enzymes and chemicals derived from krill are included in a number of dietary and medical products. ... The total krill catch this season is expected to be 150,000-180,000 tonnes, exceeding last year's total by about 40%.
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from USA Today
If you've been blaming your weight on your genes, get out and take a brisk walk. It will help fight your tendency toward overweight, a new study shows. Researchers in Great Britain studied 12 genetic variants known to increase the risk of obesity and tracked the physical activity levels of 20,430 people.
They created a genetic summary score to quantify a person's risk of obesity and then examined whether an active life could reduce the genetic influence. Findings: Physical activity can reduce the genetic tendency toward obesity by 40%, according to the research, reported Tuesday in PLoS Medicine.
"Our findings challenge the popular myth that obesity is unavoidable if it runs in the family," says senior researcher Ruth Loos of Great Britain's Medical Research Council in Cambridge. "We see this as a hopeful message."
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from New Scientist
From the relaxing effects of cannabis to the highs of LSD and ecstasy, illegal drugs are not generally associated with the lab bench. Now, for the first time in decades, that is starting to change.
For almost 40 years, mainstream research has shied away from investigating the therapeutic benefits of drugs whose recreational use is prohibited by law. But a better understanding of how these drugs work in animal studies, and the advancement of brain-imaging techniques, has sparked a swathe of new research.
What's more, clinical trials of MDMA (ecstasy), LSD and other psychoactive drugs are starting to yield some positive results. This could lead to a call for governments to take a new approach to the funding and regulation of research into the potential benefits of such chemicals.
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from USA Today
No more sunny side up. No more eggs Benedict. No more almost-set scrambled eggs. After of one of the largest egg recalls on record, critics say the egg industry is resorting to the worst tactic of all: blaming the victim. More than 1,400 illnesses now appear to be tied to an outbreak of Salmonella enteritidis definitively linked to eggs produced on two Iowa farms.
"Consumers that were sickened reportedly all ate eggs that were not properly or thoroughly cooked. Eggs need to be cooked so that the whites and yolks are firm (not runny), which should kill any bacteria," says Mitch Head, spokesman for the United Egg Producers.
The message seems to be that anyone who eats them otherwise should be aware they're eating the food-safety equivalent of steak tartare, a dish of raw, seasoned, minced beef first popularized in France. ... This isn't sitting well with food-safety advocates.
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from the New York Times (Registration Required)
Presidential elections can be fatal. Win an Academy Award and you're likely to live longer than had you been a runner-up. Interview for medical school on a rainy day, and your chances of being selected could fall. Such are some of the surprising findings of Dr. Donald A. Redelmeier, a physician-researcher and perhaps the leading debunker of preconceived notions in the medical world.
In his 20 years as a researcher, first at Stanford University, now at the University of Toronto, Dr. Redelmeier, 50, has applied scientific rigor to topics that in lesser hands might have been dismissed as quirky and iconoclastic. In doing so, his work has shattered myths and revealed some deep truths about the predictors of longevity, the organization of health care and the workings of the medical mind.
"He'll go totally against intuition, and come up with a beautiful finding," said Eldar Shafir, a professor of psychology and public affairs at Princeton University who has worked with Dr. Redelmeier on research into medical decision-making.
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from PRI's The World Science
China and Russia have just announced a plan to set up the first cross-border protection zone for the Siberian tiger. There are fewer than 500 Siberian tigers in the wild today, only about 20 of them in China. This international tiger conservation effort will attempt to protect the remaining tigers from poaching and habitat loss.
Nepal runs a program that pays local communities to protect tigers and tiger habitats. Other countries are drafting plans to protect the species as part of a new Global Tiger Recovery Program.
Can such efforts save the tiger? Or is it facing inevitable extinction? Bring your thoughts and questions to John Seidensticker, a conservation biologist at the Smithsonian's Washington National Zoological Park in Washington, DC. The discussion continues through September 13.
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from National Geographic News
Notes on the back of a 400-year-old letter have revealed a previously unknown language once spoken by indigenous peoples of northern Peru, an archaeologist says.
Penned by an unknown Spanish author and lost for four centuries, the battered piece of paper was pulled from the ruins of an ancient Spanish colonial church in 2008. But a team of scientists and linguists has only recently revealed the importance of the words written on the flip side of the letter.
The early 17th-century author had translated Spanish numbers--uno, dos, tres--and Arabic numerals into a mysterious language never seen by modern scholars.
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from the San Diego Union-Tribune (Registration Required)
RALEIGH, N.C. (Associated Press) -- An emerald so large it's being compared with the crown jewels of Russian empress Catherine the Great was pulled from a pit near corn rows at a North Carolina farm.
The nearly 65-carat emerald its finders are marketing by the name Carolina Emperor was pulled from a farm once so well known among treasure hunters that the owners charged $3 a day to shovel for small samples of the green stones. After the gem was cut and re-cut, the finished product was about one-fifth the weight of the original find, making it slightly larger than a U.S. quarter and about as heavy as a AA battery.
The emerald compares in size and quality to one surrounded by diamonds in a brooch once owned by Catherine the Great, who was empress in the 18th century, that Christie's auction house in New York sold in April for $1.65 million, said C.R. "Cap" Beesley, a New York gemologist who examined the stone.
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from BBC News Online
A team of 86 global scientists have sequenced the genetic code of the Golden Delicious apple for the first time. The DNA breakthrough could result in new and improved apple varieties which are more resistant to disease.
Scientists from 20 institutions took two years to unravel the code--the largest plant genome uncovered to date. The findings are published in the leading journal Nature Genetics.
Professor Riccardo Velasco at the Edmund Mach Foundation in Italy, who led the research team, said that sequencing the genome "would have huge implications for applied breeding." ... Kate Evans from Washington State University's Tree Fruit Research and Extension Centre said the discovery would help the "long-term sustainable production" of apples.
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from Science News
One of paleontology's most revered fossil sites now has a baby brother. Scientists have discovered a group of astonishing fossils high in the Canadian Rockies, just 40 kilometers from the famous Burgess Shale location.
A paper describing the find appears in the September issue of Geology.
Since its discovery in 1909, the Burgess Shale has yielded many thousands of fossils dating to 505 million years ago--a period often called "evolution's big bang," when animals were exploding in diverse body plans. These soft-bodied critters scurried around on the sea floor, then were buried in mudslides and exquisitely preserved.
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